The invention relates to a composition and a method for the oxidative coloring of hair, using a 1-methyl-4-isopropyl-hydroxybenzene as coupler substance.
For the coloring of hair, oxidative coloring compositions have a tremendous significance. The coloring takes place through the reaction of specific developers with specific coupler substances in the presence of a suitable oxidation agent.
As developer substances, 1,4-diaminobenzene, 2,5-diaminotoluene, 3-methyl-4-aminophenol and p-aminophenol have been employed. Among others, resorcinol, 4-chlororesorcinol, .alpha.-naphthol, 2,4-diaminotoluene, 2,4-diaminoanisole, 2,4-diaminophenoxyethanol, 2,5-dimethylphenol and m-aminophenol are used as coupler substances.
There are numerous requirements which must be met by oxidation coloring agents which are to be used for the coloring of human hair. They must be toxicologically and dermatologically suitable for such use; moreover, they must permit the achievement of coloring of the desired intensity. It is also necessary that through the combination of suitable developer and coupler components a broad palette of various color nuances might be achieved. Further, good tolerances to light, permanent wave treatments, acid and rubbing are required. In any event, the hair colorings should remain stable over a period of at least 4 to 6 weeks without negative influence from light, rubbing and chemical agents.
This large number of requirements cannot be fully satisfactorily met through the use of the known oxidation hair coloring agents. This holds true both for the phenolic coupler substances .alpha.-naphthol and 2,5-dimethylphenol and for m-phenylenediamine and derivatives 2,4-diaminoanisole, 2,4-diaminotoluene and 2,4-diaminophenoxyethanol.
On account of their physiological hazard, some of the named coupler substances, namely 2,5-dimethylphenol, 2,4-diaminoanisole and 2,4-diaminotoluene, have limited practical significance. In addition, the range in which they still are employed is ever narrower. Another physiologically deleterious coupler substance is the above-mentioned 2,4-diaminophenoxyethanol.
In addition to the noted physiological and dermatological considerations, the blue- and violet-tones which can be achieved with the coupler substances mentioned have not been truly satisfactory with respect to their being fast to wear. This is true for the blue obtained by the oxidative route through the combination of developer 1,4-diaminobenzene or 2,5-diaminotoluene with the coupler substance m-phenylenediamine: even without external influences, the color rapidly turns to red. With the use of 2,4-diaminotoluene as coupler the fast to wear properties of the coloring achieved are similarly unsatisfactory.
Much less light tolerant are the violet shades obtained with the developer/coupler combination 2,5-diaminotoluene or 1,4-diaminobenzene and .alpha.-naphthol.